Recording medium, reproduction device, program and method

Abstract

A BD-ROM has a video stream and an entry map recorded thereon. The entry map indicates a plurality of entry points (SPN_EP_start) in the video stream, in one-to-one correspondence with a plurality of entry times (PTS_EP_start) and flags (is_angle_change_point). Each flag (is_angle_change_point) indicates whether a 1picture located at a corresponding entry point is an IDR picture for causing decoder refresh or Non-IDR I picture having a reference to a preceding picture.

What is claimed is: 
     
       1. A non-transitory computer-readable recording medium having a video stream and an entry map recorded thereon, wherein
 the video stream represents one angle image contained in a multi-angle section in which a plurality of angle images have a same playback time on a playback timeline, 
 the video stream is a sequence of GOPs including an Open-GOP and a Closed-GOP, 
 in each GOP, a first picture in coding order is attached with an SPS, 
 a first picture in each Open-GOP is an intra-picture for not causing decoder refresh, 
 a first picture in each Closed-GOP is an intra-picture for causing decoder refresh, 
 the entry map indicates a plurality of entry points where a first intra-picture in each GOP is located in the video stream, in one-to-one correspondence with a plurality of entry times and flags, 
 each flag indicates whether a corresponding entry point is an angle changeable point from another angle image contained in the multi-angle section, and 
 an intra-picture for causing decoder refresh is located at each angle changeable point; 
 wherein a computer is operable to execute playback of the video stream recorded on the non-transitory computer-readable recording medium for displaying images. 
 
     
     
       2. The non-transitory computer-readable recording medium according to  claim 1 , wherein
 the video stream on the recording medium is composed of a plurality of segments, and 
 an angle changeable point coincides with a start point of a segment. 
 
     
     
       3. The non-transitory computer-readable recording medium according to  claim 2 , further having recorded thereon:
 a plurality of management information files; and 
 playback section information, wherein 
 the playback section information defines a start point and an end point of the multi-angle section in the video stream, and includes a field storing names of the management information files, and 
 the entry map is contained in one of the management information files. 
 
     
     
       4. A playback apparatus for executing playback of a video stream based on an entry map, the video stream being a sequence of GOPs including an Open-GOP and a Closed-GOP, a first picture in each GOP in coding order being attached with an SPS, the entry map indicating a plurality of entry points in the video stream in one-to-one correspondence with a plurality of entry times and flags, said playback apparatus comprising:
 a reading unit operable to read pictures contained in the video stream from a recording medium; 
 a playback unit operable to play back the read pictures; 
 a control unit operable, in response to a request to start playback from a given temporal point, to (i) specify a nearby entry time to the requested temporal point from among entry times each with a flag set to ON and (ii) cause the reading unit to read the video stream starting from an entry point corresponding to the specified entry time; 
 a picture buffer operable to store a plurality of reference pictures; 
 a decoder operable to perform motion compensation using the reference pictures; 
 a status register operable to store a value indicating an angle image to be played back out of a plurality of angle images contained in a multi-angle section and having a same playback time on a playback timeline; and 
 an update unit operable to update the value stored in the status register in accordance with a user operation, wherein 
 the recording medium has recorded thereon a plurality of management information files and playback section information, and 
 the playback section information defines a start point and an end point of the multi-angle section in the video stream, and includes a field storing names of the management information files, 
 the reading unit is operable to read a management information file indicated by the updated value of the status register, from among the management information files whose names are stored in the playback section information, and 
 the entry map used by the control unit is contained in the read management information file, 
 the video stream includes, at each entry point with the flag set to ON, an intra-picture that is a first picture in a Closed-GOP at which an angle change from another angle image contained in the multi-angle section is possible, and 
 the decoder is operable to clear content of the picture buffer when decoding a first picture in a Closed-GOP. 
 
     
     
       5. The playback apparatus according to  claim 4 , wherein:
 the recording medium has recorded thereon a plurality of AV files, 
 the video stream read by the reading unit is contained in an AV file having a same name with the read management information file, and 
 the reading unit is operable to read the video stream starting from one of a plurality of extents of the AV file, said one extent containing an entry point corresponds to the specified entry time. 
 
     
     
       6. A method for recording, onto a non-transitory computer-readable recording medium, a video stream representing one angle image contained in a multi-angle section in which a plurality of angle images have a same playback time on a playback timeline, the method comprising:
 generating volume data; 
 obtaining a recording medium on which the volume data has been recorded, wherein: 
 the volume data includes the video stream and an entry map, 
 the video stream is a sequence of GOPs including an Open-GOP and a Closed-GOP, 
 in each GOP, a first picture in coding order is attached with an SPS, 
 a first picture in each Open-GOP is an intra-picture for not causing decoder refresh, 
 a first picture in each Closed-GOP is an intra-picture for causing decoder refresh, 
 the entry map indicates a plurality of entry points where a first intra-picture in each GOP is located in the video stream, in one-to-one correspondence with a plurality of entry times and flags, and 
 each flag indicates whether a picture located at a corresponding entry point is for causing decoder refresh an angle changeable point from another angle image contained in the multi-angle section, and 
 an intra-picture for causing decoder refresh is located at each angle changeable point; 
 wherein a computer is operable to execute playback of the video stream recorded on the non-transitory computer-readable recording medium for displaying images.